Check engine light comes on???

[89hatchlx]

Not to worried about it but figured I'd ask... My check engine light comes on under hard exceloration. Around 4,500 to 5,500 rpms it comes on till i let out of the throttle. Some times it doesn't do it at all and i never see it during normal driving. Car runs great other wise. Anyone have any ideas? Heres whats the car is and what it has.

89 lx, 5.0 5speed
Performer upper and lower intake, stock heads, 65mm t/b with 65mm egr spacer, Crane Ignition, (MSD cap,rotor,wires,Coil) Trickflow Stage 1 cam, ProM 24lb injectors with Matching m/a, BBK cold air, BBK shorty headers, 3inch Flowmaster Xpipe with 3inch cat back, 337's.
Car has new IAC and Newer EGR, New ATC, New Coolant Temp Sen. Checked car for vac leaks and all can't find anything..

Any ideas could someone let me know..

 

[jrichker]

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See Troublcodes.net Trouble Codes OBD & OBD2 Trouble Codes and Technical info & Tool Store. By BAT Auto Technical

If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see EQUUS DIGITAL FORD CODE READER (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.

 

[89hatchlx]

Thanks you guys are fast lol.. I'll give it a try and see what i come up with. I'll let you know how i make out.

 

[89hatchlx]

With the enigine off i turned the key to the on position and it blinked 8 times paused then blinked 5 times. . . Does that stand for 85??


Going to test again in a min with the engine running and see what i get..

okay with the engine off the light blinked 8 times then paused then blinked 5 times..

with the engine running it blinked 3 times and then the idle increased to 1,500 rpms.. kinda fishy?

took the paper clip out started the car with it out and it idled fine.. ran both test again and the same results. sorry to be a pain but could someone put these in idiot terms lol dont know what they stand for..??

 

[jrichker]

Code 85 - CANP solenoid - The Carbon Canister solenoid is inoperative or missing. Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by grounding the gray/yellow wire to the solenoid and blowing through it.
The computer provides the ground for the solenoid. The red wire to the solenoid is always energized any time the ignition switch is in the run position.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel.

It does not weigh but a pound or so and helps richen up the cruse mixture. It draws no HP & keeps the car from smelling like gasoline in a closed garage. So with all these good things and no bad ones, why not hook it up & use it?

This is what it looks like...

The engine speed increase is normal when doing a code dump with the engine running. I recommend that you buy a Chilton's service manual for your car to get the complete procedure for the engine running diagnostic tests.

 

[89hatchlx]

Thanks for the great info i think when i deleted my smog pump i also took that off not knowing what it was.. But i saved everything so i'll be putting it back on. Thanks again for the fast reply and the extra knowledge..